Fructosyltransferases

Two extracellular D-fructans, (2- 6)-linked S-D-fructofuranan or levan and the less common corresponding (2 l)-linked polysaccharide, of the inulin type, are elaborated by different bacteria. These polysaccharides are formed from sucrose by the action of sucrose fructosyltransferases. Terminal )S-D-fructofuranosyl groups are present in some bacterial heteropolysacchar-... 

S. A. van Hijum, K. Bonting, M. J. van der Maarel, and L. Dijkhuizen, Purification of a novel fructosyltransferase from Lactobacillus reuteri strain 121 and characterization of the levan produced, FEMS Microbiol. Lett., 205 (2001) 323-328. 

J. Seibel, R. Moraru, S. Gotze, K. Buchholz, S. Na amnieh, A. Pawlowski, and H. J. Hecht, Synthesis of sucrose analogues and the mechanism of action of Bacillus subtilis fructosyltransferase (levansucrase), Carbohydr. Res., 341 (2006) 2335-2349. 

L. K. Ozimek, S. A. van Hijum, G. A. van Koningsveld, M. J. van Der Maarel, G. H. van Geel-Schutten, and L. Dijkhuizen, Site-directed mutagenesis study of the three catalytic residues of the fructosyltransferases of Lactobacillus reuteri 121, FEBS Lett., 560 (2004) 131-133. 

I. E. Baciu, H. J. Jordening, J. Seibel, and K. Buchholz, Investigations of the transfructosylation reaction by fructosyltransferase from B. subtilis NCIMB 11871 for the synthesis of the sucrose analogue galactosyl-fructoside, J. Biotechnol., 116 (2005) 347-357. 

P. S. J. Cheetam, A. J. Hacking, and M. Vlitos, Synthesis of novel disaccharides by a newly isolated fructosyltransferase from Bacillus subtilis, Enzyme Microb. Technol., 11 (1989) 212-219. 

Fructooligosaccharides (FOS) are ((32-1) fructose oligomers bound to glucose at the non-reducing end industrially produced from sucrose by fructosyltransferases (sucrose 1-fructosyl transferases EC 2.4.1.9).128... 

This enzyme [EC 2.4.1.9], also referred to as sucrose 1-fructosyltransferase, catalyzes the reaction of sucrose with [(2,l)-/3-D-fructosyl] to produce D-glucose and [(2,l)-/3-D-fructosyl]( +1). Thus, this enzyme participates in the conversion of sucrose into inulin and glucose. Other fructosyl-containing sugars can serve as substrates as well instead of sucrose. 

Dijkhuizen and coworkers identified and characterized a Lactobacillus levansucrase (systematic name sucrose [6)-P-D-fructofuranosyl-(2 ]n a-D-glucopyranoside 6-P-D-fructosyltransferase EC 2.4.1.10) from L. reuteri strain 121, which could produce a high molecular weight levan polysaccharide from fructose [207]. 

Polyfructan (inulin) of MW 30-50 million was synthesized from sucrose with fructosyltransferase (FTF, inulin sucrase from Streptococcus mutans) immobilized by photoinitiated graft copolymerization with poly(2-aminoethyl methacrylate) in the pores of a 3.0 pm microfiltration membrane (Hicke, 1999). 

Disaccharides analogous to isomaltulose, but containing other sugars in place of ot-D-glucose, can be obtained by similar bioconversions from different disaccharides.234 Sucrose analogues (galactose-fructose, xylose-fructose, fucose-fructose) have also been prepared by isomerization, catalyzed by an engineered fructosyltransferase.235,236... 

Disaccharides analogous to sucrose, but having different rings might have useful biological properties. Galactosucrose was obtained by a multistep sequence from sucrose in 27% overall yield.235 An enzymatic route to this derivative, involving the fructosyltransferase (FTF) from Bacillus subtilis NCIMB... 

In transgenic crops a specific fructosyltransferase and promoter can be selected to tailor the degree of polymerization and branching to certain needs. For example, using a Streptococcus mutans fructosyltransferase gene in which the C- or N-terminal peptide encoding portions are deleted,... 

Engels, D., Alireza, H.B., Kunz, M., Mattes, R., Munir, M., and Vogel, M., Modified Streptococcus Gene ftf and Fructosyltransferase and Their Use in Preparation of Inulin, Fructooligosaccharides, and Difructose Dianhydride for Use in Food and Feed, WO Patent 2002050257, 2002. 

Heyer, A.G. and Wendenburg, R., Gene cloning and functional characterization by heterologous expression of the fructosyltransferase on Aspergillus sydow IAM 2544, Appl. Environ. Microbiol., 67, 363-370, 2001. 

Stoop, J.M., Plant Genes for Fructosyltransferase and Their Use in the Development of Transgenic Plants with Embryos Rich in Fructan, U.S. Patent 2004073975, 2004. 

Vijn, I., Van Dijken, A., Sprenger, N., Van Dun, K., Weisbeek, P., Wiemken, A., and Smeekens, S., Fructan of the inulin neoseries is synthesized in transgenic chicory plants (Cichorium intybus L.) harboring onion (Allium cepa L.) fructan fructan 6G-fructosyltransferase, Plant J., 11, 387-398, 1997. 

Inulin biosynthesis in Jerusalem artichoke occurs via the combined action of two enzymes l-sucrose sucrose fructosyltransferase (1-SST) and l-fructan fructan fructosyltransferase (1-FFT). 1-SST catalyzes the synthesis of inulins of a low degree of polymerization, while 1-FFT catalyzes the synthesis of ffuctans of a degree of polymerization up to 50 (Sevenier et al., 2002a). High... 

Koops, A.J. and Jonker, H.H., Purification and characterization of the enzymes of fructan biosynthesis in tubers of Helianthus tuberosus Columbia. 1. Fructan fructan 1-fructosyltransferase, J. Exp. Bot., 45, 1623-1631, 1994. 

Luscher, M., Purification and characterization of fructamfructan fructosyltransferase from Jerusalem artichoke, New Phytologist, 123, 717-724, 1993. 

FIGURE 10.19 Deduced amino acid sequence for fructan fructan transferase (FFT) and sucrose sucrose 1-fructosyltransferase (SST). (From van der Meer, I.M. et al., Plant /., 15, 489-500, 1998.) Amino acids in bold represent homology between FFT and SST. Symbols A = alanine C = cysteine D = aspartate E = glutamate F = phenylalanine G = glycine H = histidine I = isoleucine K = lysine L = leucine M = methionine N = asparagine P = proline Q = glutamine R = arginine S = serine T = threonine V = valine W = tryptophan and Y = tyrosine. 

FIGURE 10.20 The action of fructan 1-exohydrolase and fructan fructan 1-fructosyltransferase in dormant and sprouting tubers on inulin depolymerization. Abbreviations 1-feh = fructan 1-exohydrolase 1-fft = fructan fructan 1-fructosyltransferase hk = hexokinase spp = sucrose phosphate phosphatase sps = sucrose phosphate synthase GF = sucrose G = glucose F = fructose GFF = 1-ketose GF-P = sucrose phosphate UDP-G = uridine diphosphate glucose F-6-P = fructose-6-phosphate. 

Koops, A.J., Sevenier, R., Van Tunen Arjen, J., and De Leenheer, L., Transgenic Plants Comprising 1-SST and 1-FFT Fructosyltransferase Genes for a Modified Inulin Production Profile, European Patent 952222, 1999. 

Leuscher, M., Erdin, C., Sprenger, N., Hochstrasser, U., Boiler, T., and Wiemken, A., Inulin synthesis by a combination of purified fructosyltransferases from tubers of Helianthus tuberosus, FEBS Lett., 385, 39-42, 1996. 

Scott, R.W., Jefford, T.G., and Edelman, J., Sucrose fructosyltransferase from higher plant tissues, Biochem. J 100, 23P-24P, 1966. 

Shiomi, N., Properties of fructosyltransferases involved in the synthesis of fructan in Liliaceous plants, J. Plant Physiol., 134, 151-155, 1989. 

Vergauwen, R., Van Laere, A., and Van den Ende, W., Properties of fructan fructan 1-fructosyltransferase (1-FFT) from Cichorium intybus L. and Echinops ritro L., two Asteraseae plants storing greatly different types of inulin, Plant Physiol., 133, 391 401, 2003. 

Keywords Biocatalysis, Enzyme engineering, Fructosyltransferases, Glucosyl-transferases, Immobilization, Oligosaccharides, Reaction engineering... 

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